Chicken or Sardine Sandwich With Black Beans and Avocado

This spicy sandwich is inspired by one often served in the city of Xalapa in the Mexican state of Veracruz. It’s called pambazo, which is also the name of the flaky roll it’s made with. The bread is spread with pureed black beans and traditionally filled with shredded chicken, chorizo or sardines (the sardine version is not easy to find today), as well as lettuce, tomato, avocado, onion and pickled chipotles. Since tomatoes aren’t yet in season, they’re optional here.

1. Mash the black beans, and make sure they’re well seasoned. Spread over the top and bottom halves of the hamburger bun. Layer the avocado over the beans on the bottom half of the bun, and sprinkle with salt and lime juice to taste. Top the avocado slices with the chicken or sardine fillets and the sliced chipotle. Toss the salad greens with the vinegar or additional lime juice until thoroughly coated, and pile on top of the chicken or sardines and chipotles. Top with a layer of sliced tomatoes and onion if desired, and cover with the top bun. Press down and wrap the sandwich tightly in plastic wrap. If possible, allow to sit for 10 to 15 minutes, or for several hours in the refrigerator, before eating.